package org.zty.util;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class SetCharacterEncodingFilter
  implements Filter
{
  protected String encoding = null;

  protected FilterConfig filterConfig = null;

  protected boolean ignore = true;

  public void destroy()
  {
    this.encoding = null;
    this.filterConfig = null;
  }

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    throws IOException, ServletException
  {
    if ((this.ignore) || (request.getCharacterEncoding() == null)) {
      String encoding = selectEncoding(request);
      if (encoding != null) {
        request.setCharacterEncoding(encoding);
      }
    }

    chain.doFilter(request, response);
  }

  public void init(FilterConfig filterConfig)
    throws ServletException
  {
    this.filterConfig = filterConfig;
    this.encoding = filterConfig.getInitParameter("encoding");
    String value = filterConfig.getInitParameter("ignore");
    if (value == null)
      this.ignore = true;
    else if (value.equalsIgnoreCase("true"))
      this.ignore = true;
    else if (value.equalsIgnoreCase("yes"))
      this.ignore = true;
    else
      this.ignore = false;
  }

  protected String selectEncoding(ServletRequest request)
  {
    return this.encoding;
  }
}